Improvement in stair-builders  tools



T. SIMONS'ON.

. A STAIR-BUILDERS" TOOLS.

No. 183,222. Patented. Oct. 10. 1876 VENTUB 1/ I MM BY ATTUBNEYS.

JAMES Roscooo & co. BOSTON NITED STATEs PATENT Qirrrcn THEODORESIMONSON, OF HILLSBO ROUGH, OHIO.

IMPROVEMENT IN STAlR-BUILDERS TOOLS.

Specification forming part of Letters Patent No. 183,222, dated October10, 1876; application filed vJune 20, 1876.

To all whom it may concern:

Be it known that I, THEODORE SIMONsON, of Hillsborough, in the county ofHighland and State of Ohio, have invented a new and ImprovedStair-Builders Tool, of which the following is a specification Figure 1is a perspective view. Fig. 2 is a side elevation. Fig. 3 is a detailview of one of the parts.

Similar letters of reference indicate corresponding parts.

My invention relates to the class of tools used by stair-builders ingetting the pitch, bevels, and length of wreaths or twists in hand-rails5 and it consists of two bars of wood or other material hinged orpivoted together, having at their free ends adjustable slotted pieces,which are held in place by thumb-screws, the object being to provide aninstrument which will facilitate the work referred to by avoiding thecomplication of geometric lines, usually resorted to, and accomplishingthe desired result with two simple lines.

To do this I provide two pieces of board of equal length, and hinge themtogether in such a manner as to present a sharp angle, as shown at A inFig. 1. These boards are held in any required position by slotted piecesand a thumb-screw, placed in the angle formed by the boards. This deviceis placed on the ground-plan of the stairway, with the face side tolines tangent to the circle formed by the center of the hand-rail. Aline is then drawn on each piece of board at the required pitch, givingthe pitch of each tangent. These are the only lines required.

The device just described is auxiliary to my improvement describedbelow.

Two bars or arms, a a, of wood or other suitable material, are jointedor pivoted together by the thumb-screw b. Slotted pieces 0 c areattached to the ends of the bars a a by thumb-screws d d, and are heldat right angles with the bars.

The manner of using my device is as follows: The bars a a are placed onthe pitchlines on the boards previously described, the upper surface ofthe bar a and the under surface of the bar a being placed on the lines.The thumb-screw b is then tightened, holding the bars a a rigidly at therequired angle. At the same time the adjust-able pieces 0 c at the endsof the bars are placed against the sides of the boards and tightened bythe thumb-screws cl d. The angle between the bars or arms a a is the oneby which the joints of the twist may be squared, and the adjustablepieces 0 0 give the bevel for the end or joint of the twist.

Having thus described my invention, I claim as new and desire to secureby Letters latent The combination of the bars a an, adjustable pieces 0c, and the screws b, d, and (1, substantially as shown and described.

THEODORE SIMON SON.

Witnesses:

WM. HoYT, R. R. WATTS.

